Shannon, a 14-year-old who lives in Massachusetts, has amblyopia, a condition sometimes referred to as “lazy eye.”

Patients’ best hope for correcting amblyopia is before they turn about 8 years old. Those who don’t get treatment early enough—or for whom treatment doesn’t work—usually end up living with the problem forever.

Shannon is one of those people. Her entire life, she’s worn glasses with a thin non-prescription lens on one side, and a thick corrective lens on the other. As a toddler, her parents tried to make her wear therapeutic eye patches, but she would fling them off.

A few months ago, Shannon enrolled in a clinical study at Boston Children’s Hospital for which she’s taking donepezil, a drug that’s typically used to treat Alzheimer’s. Donepezil is a cholinesterase inhibitor, meaning it increases the amount of acetylcholine circulating around nerve endings. It's been shown to improve memory function in some patients with dementia.

But of course, Shannon doesn’t have memory problems. Her team of doctors is instead using the donepezil to encourage her brain to learn new skills as quickly and nimbly as an infant’s would. Shannon's vision has improved markedly over the past four months, her mother told me by phone.

Takao Hensch, a Harvard professor of cellular biology who is part of the Boston Children’s team, has found that behavioral drugs like donepezil can help return the chemistry of the brain to so-called “critical periods” in its development—the times during early childhood when the brain was rapidly growing. Critical periods help explain why children younger than about 7 can pick up new skills, like language and music, much faster than adults can. This is why you see parents attempting to plant foreign languages in their kids while they’re still in Pampers. It’s much easier than trying to conjugate French verbs for the first time when you’re 30.

Hensch and his colleagues have already found that valproate, an epilepsy drug, can help tone-deaf adults learn to differentiate music notes. In a study published in December in the journal Frontiers in Systems Neuroscience, a team of researchers including Hensch administered valproate or a placebo to 24 men with no music experience and then trained them to label music notes. Those who took the valproate were later able to correctly identify 5.09 music notes on average, compared with 3.5 in the control group.

There were several flaws in the study—the sample size was small, and it’s possible that some of the men had a genetic predisposition toward music.

Still, the effect size was promising enough for Hensch to attempt new experiments with other drugs and different types of traits.

The psych meds work by boosting the molecules, such as serotonin and acetylcholine, that are normally dampened during adulthood. The extra surge of chemicals aids in the rewiring process.

Women who take valproate (Depacon) during pregnancy may increase the risk of childhood autism and its spectrum disorders in their children, a population-based study showed.

In utero exposure to the drug was associated with a five-fold elevated risk of autism and three-fold elevated risk for autism spectrum disorder, Jakob Christensen, PhD, of Denmark's Aarhus University Hospital, and colleagues found.

The American Academy of Neurology recommends avoiding valproate in pregnancy whenever possible due to cognitive and physical birth defect problems for children exposed in utero.

Pregnant women who took a popular epilepsy drug, also widely used to treat migraines, pain and psychiatric disorders, had children whose I.Q. scores were significantly lower than those whose mothers took a different antiseizure medication, a new study has found.

The drug, valproate, sold generically and under the brand name Depakote, remains the second-most-popular antiseizure medication used for epilepsy, but earlier studies found that use during pregnancy also increased the risk of developmental delays and major malformations.

The risks that other epilepsy drugs may pose are not clear, experts say. While some are likely to be safer than others, there have not been enough studies to guide patients and their doctors. About half of the women who take valproate are not epileptics.

The new study is to be published on Thursday in The New England Journal of Medicine.

Three-year-olds whose mothers had taken valproate during pregnancy had I.Q. scores that were nine points lower on average than children whose mothers had taken a different antiseizure medication, lamotrigine. The I.Q. scores of toddlers whose mothers took valproate were also lower than scores of children whose mothers took two other antiseizure medications, phenytoin and carbamazepine.

Physicians involved in the study warned that valproate should never be the first choice for use in women of childbearing age, though exceptions may be made if a woman’s epileptic seizures cannot be controlled with other available medications.

Some 13,000 to 21,000 babies each year are born to women with epilepsy, and the vast majority are healthy, researchers and advocates emphasized.

Experts warned that women should not stop taking valproate without talking to their doctors.

“It’s important to stress to readers that if they become frightened, they should not simply stop taking the drug, because that can be even more dangerous,” said Eric Hargis, president of the Epilepsy Foundation in Washington.